[Citroënbender]

If the head comes off, it introduces liability for the resealing.

I’d more likely drop the whole motor if reliably “square” access from above starts to look impossible. That would also allow the cam box to be set aside more easily for better jig-work. The shop probably doesn’t have a chain breaker to suit, but everything else would be regular fare.

The whole situation has come about first by poor design and secondly poor thread preparation prior the last repair - it’s known these motors have issues with the injector bolts and chasing their holes fully clean is essential. Plus new bolts every time.